(1) Field of the Invention
The present invention relates to an embossed sheet which is prepared by embossing a transparent sheet with some patterns. The transparent sheet used for this purpose in the present invention comprises a specific polyolefin resin composition and has excellent workability in embossing operation in easiness in the formation of embossing patterns and the durability of embossing patterns at high temperatures. The invention further relates to the laminate of the embossed sheet and a method for producing them. The term "sheet" hereinafter referred to includes "film" and the like.
(2) Prior Art
The materials made of polyvinyl chloride have been used as decorative material, interior wall material and the like made by using an embossed sheet having decorative patterns. However, because of the trouble of generating noxious gases when they are incinerated, embossed sheet made of polyolefin resin are recently used in place of them. The polyolefin embossed sheet is excellent in appearance and workability in manufacturing and the field of its uses expanded recently and the demands for the more agreeable appearance increased. It is, however, considered that the polyolefin embossed sheet is not always satisfactory in the following points:
(1) Stability in the wide variety of changes of environmental temperature,
(2) Adaptability for embossing with complicated patterns, in other words, workability in embossing,
(3) Resistance to whitening in a secondary processing or when it is subjected to shocks, in the case that the thickness of sheet is increased in order to form deep embossing patterns, and
(4) Good transparency or other property.
It is, therefore, the object of the present invention to provide a polyolefin embossed sheet which is free from the above problems and which also maintains proper balances among the characteristic features of conventional ones such as softness, transparency, yield strength, and scratch resistance (surface hardness). The object of the present invention is to provide also the laminate made by using the embossed sheet and a method for producing the laminate by effectively taking advantage of the excellent workability in the embossing process of sheet materials.